Right on cue, Samsung announced the brand new Galaxy S4 at a press event at New York’s Radio City Music Hall. Getting straight to the specs, The S4 has a 5-inch 1080p HD display with 441ppi, a 1.9 GHz quad-core Snapdragon 600 processor (or 1.8 GHz Exynos Octa-core processor in select countries/markets), 2GB of RAM, a 13 megapixel camera, and Android 4.2.2 which is the latest version at this point in time. The S4 is also thinner at 7.9mm and lighter at 130g.

The Galaxy S4 has a bevy of new software features which I’ll go into a separate article. The S4 will be available in Black Mist and Frost White and it will launch on all four major US carriers in addition to over 300 more internationally beginning at the end of April.

A set of screenshots have leaked, purporting to be from the unannounced Galaxy S IV which is set to be announced next Friday in New York.

The first screenshot shows the new TouchWiz home screen which looks to be relatively unchanged aside from a transparent status and some icon design tweaks.The next image shows the new TouchWiz settings application which looks to use a light-gray background as opposed to the black background on the Galaxy S III. It also separates related settings into tabs at the top of the screen.

The third screenshot shows the settings for the new eye-tracking features which were recently outed in a report by the New York Times. The new features are:

Smart Rotation: Screen orientation adjusts to your angle of sight

Smart Pause: The devices pauses videos when it detects your head moving away from the screen

Smart Scroll: The screen will start to scroll automatically if the device detects that you are looking at the screen

The last images show the device information which confirms the S IV will include a quad-core 1.8 GHz processor, a 13 megapixel camera, and a 5-inch 1080p display. Screenshots leaked earlier today showing off the same features but on a Galaxy S III running the latest version of Samsung’s TouchWiz.

In an attempt to steal the spotlight at MWC 2013 today, Samsung began distributing both paper invites (at MWC) and email invites to their first Unpacked event which the company will be holding on March 14th in New York. The invite reads “Ready 4 the show” as well as “Come and meet the next Galaxy“.

A Samsung representative told Reuters that “it will be the first U.S. launch of Samsung’s flagship Galaxy smartphone in three years”. JK Shin, Samsung’s Mobile Head, told Edaily that the company was forced to move the event location to the States after being “bombarded with requests” from US carriers. The Galaxy S IV is expected to launch with a 5-inch 1080p display, either a quad- or octo-core processor with 2GB of RAM, and a 13 megapixel camera.

What looks to be a press shot of the upcoming Galaxy S IV has been spotted on Picasa (posted by user Desmond Ma) and it seems to have been there since late last month without being noticed. The image shows a slightly taller and less rounded device with the TouchWiz home screen, typical Samsung branding, and a larger, more rectangular home button. Whether it’s legit or not is unknown, but take it with a grain of salt. Keep in mind, several alleged press shots leaked last year for the Galaxy S III and a couple have leaked thus far for the S IV. The image, which can be seen above, has since been removed by the user.

In addition to the image above, more details regarding the Galaxy S IV have leaked. SamMobile says the device is being worked on under the code name “Altius J” with a model number of GT-I9500, will come in black and white, and will supposedly ship during week 16, which is the week of April 15th. Samsung will also be offering a wireless charging dock and back cover to charge the 2600 mAh battery in a more unique way, as seen with the Palm Pre and others.

Samsung’s President of Mobile Communications, JK Shin, recently confirmed that the Galaxy S IV would not be unveiled at MWC next month but rather at a separate event, which is speculated to be held on March 22nd “at Apple’s doorstep” in the US. As a side-note, JK Shin apparently also said the Galaxy Note 8.0 would be announced at MWC.

A new report today suggests Samsung will be releasing the Galaxy S IV in April with S Pen functionality as seen with the Galaxy Note. The Galaxy S IV would be the first device in the Galaxy S line to feature the S Pen, which allows for advanced stylus capabilities such as handwriting, note taking, and drawing.

The Galaxy S IV is also rumored to include a slightly larger, 5-inch 1080p display, a 13 megapixel camera, some version of Jelly Bean (most likely 4.2), and a quad-core Exynos processor. The device could possibly measure in at a slightly thicker 9.2mm, compared to the 8.6mm of the Galaxy SIII.